Hi, I’ve been having this problem since i started rendering Minecraft models in my scenes.
As you can see from the picture, the beak/nose of my Minecraft characters are being illuminated while the layer behind it is darker in comparison. This makes the character faces look really awkward.
Im not sure if this is a problem with the rig or with the texture settings. 
I have tried to Google for a solution but to no avail.
So far everything is fine apart from this problem.
I would really appreciate any help, i just started rendering these things in Blender 1 day ago. 
If any files are needed i will gladly upload them.
Thanks